1.Specilizing in kovar material 2. Have ISO9001:2008 certificate 3. Supply RoHs,Test Report 4. Professional manufacturers
NOTE:
A Nickel-Iron-Cobalt, controlled expansion alloy containing 29% Nickel. Its coefficient of expansion (which decreases with rising temperature to the inflection point), matches the expansion rate of borosilicate glasses and aluminia ceramics. Applications include glass to metal seals in applications requiring high reliability or resistance to thermal shock, ie. high-power transmitting valves, transistor leads and heaters and photography flash bulbs.
Alloy grades and chemical composition consistent with the provisions of table
the chemical composition of Kovar(%) | ||||||||||
C | P | S | Mn | Si | Cu | Cr | Mo | Ni | Co | Fe |
Not more than≤ | ||||||||||
0.03 | 0.020 | 0.020 | 0.5 | 0.30 | 0.20 | 0.20 | 0.20 | 28.5-29.5 | 16.8-17.8 | Balance |
The tensile strength of wire in line with the provisions of Table
Status code | State | Tensile strength,N/mm2 |
R 1/4I 1/2I 3/4I I | Soft state 1/4 Hard state 1/2 Hard state 3/4 Hard state Hard state
| <585 585725 655795 725860 >860 |
Strip tensile strength in line with the provisions of Table
Status code | State | Tensile strength,N/mm2 |
R 1/4I 1/2I 3/4I I | Soft state 1/4 Hard state 1/2 Hard state 3/4 Hard state Hard state | <570 520630 590700 600770 >700 |
Alloy Grades | Specimen heat treatment system | The average linear expansion coefficient α,10-6/ oC | ||
20-300 oC | 20-400 oC | 20-450 oC | ||
kovar | In hydrogen atmosphere heated to 900 ± 20 oC, insulation 1h, and then heated to 1100 ± 20 oC, insulation 15min, to not more than 5 oC / min rate of cooling to below 200 oC released | ----- | 4.6-5.2 | 5.1-5.5 |
Alloy average linear expansion coefficient in line with the provisions of Schedule IV
Alloy typical expansion coefficient
Alloy Grades
| The average linear expansion coefficient α,10-6/ oC | |||||||
20-200 oC | 20-300 oC | 20-400 oC | 20-450 oC | 20-500 oC | 20-600 oC | 20-700 oC | 20-800 oC | |
kovar | 5.9 | 5.3 | 5.1 | 5.3 | 6.2 | 7.8 | 9.2 | 10.2 |
Note: The values in the table are for reference only.
Specification: Plate, sheet, strip, rod, bar, wire, tube.
kovar square tube
